Mortgage Banking Activities, Components of Loans Held For Sale (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended	6 Months Ended
Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011	Dec. 31, 2011
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
General number of days outstanding for residential mortgage commitments, minimum (in days)			60D
General number of days outstanding for residential mortgage commitments, maximum (in days)			90D
General number of days for delivery of loans, for which the price is set by forward sales contracts, minimum (in days)			60D
General number of days for delivery of loans, for which the price is set by forward sales contracts, maximum (in days)			90D
Number of days for past due loans (in days)			90D
Components of Residential Mortgages Held For Sale Gross, Fair Value	$ 259,174	$ 169,609	$ 259,174	$ 169,609	$ 188,125
Mortgage and Marketing Revenue [Abstract]
Total originating and marketing revenue	29,689	9,409	52,770	16,938
Servicing revenue	9,859	9,947	19,856	19,774
Mortgage banking revenue	39,548	19,356	72,626	36,712
Residential Mortgage Loans Held For Sale Gross [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	247,893	167,300	247,893	167,300	184,816
Residential Mortgage Loans Held For Sale Unpaid Principal Balance, Gross	236,160	162,579	236,160	162,579	177,319
Mortgage and Marketing Revenue [Abstract]
Total originating and marketing revenue	27,706	10,037	44,798	23,373
Residential Mortgage Loan Commitments [Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	15,807	2,793	15,807	2,793	6,597
Residential Mortgage Loans Held For Sale Unpaid Principal Balance, Gross	392,247	156,209	392,247	156,209	189,770
Mortgage and Marketing Revenue [Abstract]
Total originating and marketing revenue	6,900	(702)	9,210	542
Forward Sales Contracts[Member]
Schedule of Residential Mortgage Loans Held For Sale [Line Items]
Components of Residential Mortgages Held For Sale Gross, Fair Value	(4,526)	(484)	(4,526)	(484)	(3,288)
Residential Mortgage Loans Held For Sale Unpaid Principal Balance, Gross	605,856	302,526	605,856	302,526	349,447
Mortgage and Marketing Revenue [Abstract]
Total originating and marketing revenue	$ (4,917)	$ 74	$ (1,238)	$ (6,977)

Maximum number of days for delivery of forward sales contracts.

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Maximum number of days outstanding for residential mortgage commitments to purchase.

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Minimum number of days for delivery of forward sales contracts.

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Minimum number of days outstanding for residential mortgage commitments to purchase.

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Noninterest income derived from the sale and changes in fair value of residential mortgage loans held for sale and fees for servicing of residential mortgage loans held by third parties. Also includes changes in the fair value of residential mortgage loan commitments and forward sales commitments considered to be derivative instruments.

+ References

No definition available.

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Number of days past due for residential mortgage loans

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Total gain (loss) on mortgage loans held for sale, including mortgage loan commitments and forward sales contracts.

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No definition available.

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Unpaid principal balance of loans held for sale.

+ References

No definition available.

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Carrying amount of mortgage loans to individuals not classified as held for investment but are held-for-sale.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section 45

-Paragraph 1

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-Topic 942

-SubTopic 210

-Section S99

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-Subparagraph (SX 210.9-03.7(a)(3))

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-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Subsection I

-Paragraph 8

-Subparagraph h

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Permanent Investor

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-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 65

-Paragraph 1, 34

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Income from servicing real estate mortgages, credit cards, and other financial assets held by others. Also include any premiums received in lieu of regular servicing fees on such loans only as earned over the life of the loans. May also be net of any related impairment of fair value of capitalized service costs.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher OTS

-Name Federal Regulation (FR)

-Number Title 12

-Chapter V

-Section 563c.102

-Paragraph 13

-Subsection II

-LegacyDoc This is a non-GAAP reference that was included in the 2009 taxonomy. It will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph 13

-Article 9

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-Name Accounting Standards Codification

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-Subparagraph (SX 210.9-04.13 (d))

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